Sign header



FIG. 1 is an isometric view of a sign header;

FIG. 2 is a right end view thereof;

FIG. 3 is a left end view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a back view thereof; and,

FIG. 7 is a front view thereof.

In the drawings, broken lines represent environment and features which form no part of the claimed design. 

The ornamental design for a sign header, as shown and described. 